Features of Acoustic Wave Propagation in Narrow Pipes of Variable Cross-Section, Allowing for Added Mass

The phenomena arising during the propagation of acoustic waves in narrow tubes with variable cross sections are studied. A special law of cross-sectional variation is defined for the tube. The mode of wave tunneling through a gradual narrowing is investigated. The influence of the added mass on the boundaries of the narrowing area of the tube is considered. The frequency dependences of the coefficient of wave transmission over energy are constructed with allowance for the added mass. Features of discribing dissipative effects in tubes are noted.